Configuring Dns Naptr Records - TANDBERG Gatekeeper User Manual

TANDBERG Gatekeeper User Guide
10.3.

Configuring DNS NAPTR Records

ENUM relies on the presence of NAPTR records, as defined by RFC 2915 [7]. This is used to obtain an
H.323 URI from the E.164 number. The record format that the Gatekeeper supports is:
;; order flag preference service regex replacement
IN NAPTR 10 100 "u" "E2U+h323" "!^(.*)$!h323:\1@example.com!" .
where:
order(10) and preference(100) determine the order in which NAPTR records will be processed:
Lowest order first, with lowest preference being processed first in the case of matching order.
flag (u) determines the interpretation of the other fields in this record. Only the value u is supported.
service states that this record is intended to describe E.164 to URI conversion for H.323. Its value
must be E2U+h323.
regex describes the conversion from the given E.164 number to an H.323 URI. ! is a field separator.
The first part: ^(.*)$ represents the entire E.164 number. The second part:
h323:\1@example.com represents the H.323 URI that will be generated. In the above example the
E.164 number will be concatenated with @example.com, e.g. 1234 will be mapped to
1234@example.com.
The last field of the NAPTR record, replacement, is not used and should be set to . (i.e. the full stop
character).
Once the DNS NAPTR (for the ENUM lookup) and SRV (for the corresponding H.323 URI lookup) are
present, ENUM dialing should be possible. To verify your configuration, use the locate command to try
and resolve an E.164 alias.
Page 46 of 105